A LUMPED-PARAMETER METHOD IN THE NONLINEAR-ANALYSIS OF FLEXIBLE MULTIBODY SYSTEMS

A lumped parameter method is presented in this paper. The method can be used in the nonlinear dynamic analysis of a flexible multibody system. The geometrical nonlinearity of a flexible body is shown to be automatically included in the governing dynamic equations. This lumped parameter method is called the finite segment method. The elastic parameters between two adjacent segments are evaluated. For straight and tapered segments, these parameters are listed in tables in the Appendix for quick and easy reference. To describe the topology of a multibody system a configuration matrix is introduced. The matrix can be generated from lower body array automatically by a FORTRAN subroutine presented in this paper in order to avoid the tedious manual derivation of the configuration matrix. To show the validation of the method an example is presented. The numerical results are favorably compared with analytical results. Since the geometrical nonlinearity of the flexible body is shown to be automatically included, the dynamic stiffening due to the overall nonlinear dynamic motion is automatically captured.